I am following ag_streak build and am considering going the same route. A couple of years ago I built a canoe using the "stitch and glue" method. It turned out great! Very strong and light. Basically with the stitch and glue method you hold together the shell with light gauge copper wire (stitch) and then bind it all together with epoxy and fiberglass cloth.

Ag Streak, I see that you have fiberglass listed, but the tub looks pretty nice in ply! Is that a mold, or will you glass over the wood? Can't wait to see where this goes.

I've been thinking of old aircraft construction for a tub, wooden framework and doped fabric. Or canoe-like, with ply bulkheads, wood strips, and glass over the wood.

And in a straight-up thread redirection, can I get some opinions about whether crashworthiness is a consideration in a tub? It seems like not so much, much like a motorbike itself.

Thanks, guys... Not a mold. I'm going to have it glassed right over the structure you see. I spoke to a friend in the boat building trade yesterday, and he's going to do it for me. When I finish the framing, I'll drop it off with him. He's going to use WEST-like epoxy inside and out (same stuff but a different brand he recommends), tape all the seams inside, wrap it in a layer or two of cloth on the outside, and either gelcoat or Imron it gloss black.

A couple of thoughts... I think crash worthiness will be adequate. The glass cloth will provide containment if it ever crashes with enough force to smash the wood. I'm not worried.

Also, I thought about the strip-building technique too, and I think it would be beautiful to leave it bright-finished, but both it and stitch and glue would result in a really LIGHT structure. I WANT the weight so I don't have to engineer in any ballast.

Sounds like a great plan. I've got the technology for woodworking and some experience with fiberglass, not so much equipped to weld.

I've been thinking about the crash thing, and I've decided that the best I can really hope for in a practical sense is to avoid causing the occupant more injury than they'd have if they were on the back of the bike. Thinking back to Senna's crash I'll pay special attention to keeping the struts, etc. from going through the tub. That could be messy.

This is a very helpful thread. Unfortunately I still can't decide whether to go with a new Ural or search for a good pre-made unit for half the cost. A lot of good ideas here though.

I wish I had done more research initially I didn't know the correct questions to ask, like how much wheel lead does it have and does it have any trail reduction or steering mods.
Ural's are fine little tractors if your reasonably mechanical and not in a hurry.There really is no other turn key sidecar operation that's remotely affordable.
Which leads to staring out with a used rig and improving it, the important bit would be to decide how you want to use it. Off pavement will require more suspension like the GS or Adv rigs for comfort and they will not be so willing to run 75 plus for long periods on the interstate , they'll do it but economy and comfort will be sacrificed.I would suspect Claude, Jay and Hannigan would like you to spend 8-10K plus a pretty nice motorcycle , and that will not include automotive wheels at both ends etc.
Road sidecars do fine on gravel roads but not at the speeds the adv rigs will go and one needs to be careful with them, on my GS based rig it's not unusual to be over 50 all the time on gravel.
Onward and forward.DB

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